1. Field of the Invention
The present invention relates to a digital filter, digital signal processing method, and communication apparatus.
2. Description of the Related Art
In a case where m bit data are made into m x bit data by an x-time interpolation circuit, and a digital signal process is carried out with the m*x bit data inputted into a digital filter, the number of delay elements (stages of a shift register) which constitutes a digital filter is increased in proportion to the interpolation ration x. Furthermore, the operating frequency of the digital filter is multiplied x times. Accordingly, the consumption power of the digital filter is increased, and if the digital filter is placed on integrated circuits, the area of occupation thereof is also increased.
Furthermore, in a case where serial data of a plurality of series are digitally signal-processed in parallel to each other in each of the series, it is necessary to prepare a plurality of digital filters, thereby resulting in a further increase in the consumption power and in the area of occupation on the integrated circuit chips.